This investigation supplements earlier studies done by SRI in collaboration with Dr. Bowen and Dr. Mirth to develop a fluoride releasing device for intraoral use. The safety and pharmacokinetics of the device is being evaluated preliminary to possible clinical studies of its anticaries benefits. Preliminary studies in the subhuman primate and in humans suggest that the appliance will adhere to the teeth and release fluoride at the appropriate rate. Compared with pretest levels the concentration of fluoride in saliva showed a five to tenfold increase whereas the increase of fluoride in the serum and urine was less than twofold.